Conventionally, as a radiation detector, a photon counting type which detects radiation by generating output signals corresponding to energy of radiation photons composing incident radiation, and counting the generated output signals for a predetermined time, is known. As such a photon counting type radiation detector, for example, there are radiation detectors of Patent documents 1 through 3.
The radiation detecting device (radiation detector) of the Patent document 1 pulse-height-discriminates output signals generated by detecting radiation with a semiconductor sensor and corrects outputs from the respective discriminators according to photon energy dependence of dose sensitivity of the sensor. By applying this correction, the detection sensitivity in the whole energy range detectable by the semiconductor sensor is equalized. In the radiation detector of Patent document 2, by setting energy windows with different energy window widths for radiation incident positions, the energy spectral influence depending on the incident position is corrected. Further, in the radiation detector of Patent document 3, crosstalk of a first count corresponding to the first main energy window is corrected based on the second count corresponding to the second sub-energy window and a ratio of the width of the first main energy window to the width of the second sub-energy window.
Patent document 1: Japanese Published Examined Patent Application No. H07-11575
Patent document 2: Japanese Published Unexamined Patent Application No. H09-269377
Patent document 3: Japanese Published Unexamined Patent Application No. H09-318755